We installed concrete with foam boards that were supplied to us by our fiberglass pool contractor. We did not use the pool contractor’s concrete guy to pour our concrete as he was like 2 months out (big mistake). The cement did not get down far enough in places and you can see the plastic piece that stays in place and the concrete is almost crumbling in places. We did not use block/stone coping. We poured the concrete up to the installed foam boards. How do we repair this? I cannot upload a picture. This is essentially what it looks like:

hopefully that link works. Thanks for any suggestions on fixing this.